1. Field of the Invention
The present invention relates to laser processing machines for processing sheet-like workpieces, such as sheet metal, by various methods such as cutting and piercing by the use of laser beams produced by laser resonators.
More particularly, the present invention relates to a method of and an apparatus for aligning the axes of the assisting gas nozzles, which jet out an assisting gas toward the workpieces, with the laser beam axes in such laser processing machines.
2. Description of the Prior Art
Laser beams are widely used in industry to process a variety of metallic and nonmetallic materials such as iron, nickel, plastic, rubber and glass. In laser processing, the laser beam is produced by a laser resonator and is applied, together with an assisting gas such as oxygen gas (O.sub.2), to a material to be processed. The laser beam is applied to the material after being focussed by a condensing lens.
In a laser processing machine which processes workpieces by emitting a laser beam and simultaneously jetting out the assisting gas as mentioned above, it is necessary, in order to perform stabilized laser processing (cutting, etc.), that the optical axis of the laser beam (laser beam axis) and the center axis of the assisting gas nozzle (nozzle axial center) be in alignment. However, since the mechanism of an optical system of a laser beam and that of the nozzle system of the assisting gas in the laser processing machine must be made independent of each other, the axis of the assisting gas nozzle is not always aligned with the laser beam axis during machine operation. In the prior art, therefore, it was necessary that an operator observe a workpiece processed during a test operation and align the axis of an assisting gas nozzle with a laser beam axis. This procedure is very time consuming, involves considerable handling and effort, and depends heavily upon the skill of the operator.